With the increase in the amount of transmission information, optical interconnect lines for transmitting optical signals in addition to electrical interconnect lines have been used in recent electronic devices and the like. Specifically, an opto-electric hybrid module including an opto-electric hybrid unit in which an optical waveguide serving as optical interconnect lines is stacked on an electric circuit board having electrical interconnect lines formed thereon, and an optical element unit in which an optical element such as a light-emitting element for converting an electric signal into an optical signal and a light-receiving element for converting an optical signal into an electric signal is mounted is incorporated in such an electronic device as described above.
In the opto-electric hybrid module, it is necessary that light emitted from the light-emitting element enters one end surface (light entrance) of each core (optical interconnect line) of the optical waveguide and that the light-receiving element receives light exiting from the other end surface (light exit) of each core. It is hence necessary that the optical elements (light-emitting element and light-receiving element) and the cores are aligned with each other so as to be capable of light propagation.
A method capable of simply aligning the optical element and the core with each other has been hitherto proposed (see PTL 1, for example). In this method, an alignment member having an aligning hole is attached to an end portion of an optical waveguide, and an aligning pin for fitting engagement with the hole is formed in an optical element unit. By bringing the hole of the alignment member and the pin of the optical element unit into fitting engagement with each other, this method automatically aligns the core of the optical waveguide and the optical element with each other so as to be capable of light propagation.